Kiama Downs siblings Cooper and Tahlia Collinge will head to the birthplace of Australian surfing to compete against some of the nation’s top up-and-coming groms.

The Australian Open of Surfing Sydney Grom Challenge will take place at Manly Beach on February 25 and 26.

The AOS Sydney Grom Challenge is part of the 2017 Australian Open of Surfing, which is touted as Australia’s biggest lifestyle and action sports festival, incorporating 300 of the world’s top athletes across surf, BMX and sport.

The second ever Australian Open of Surfing Sydney Grom Challenge will comprise four divisions – under-16 boys and girls and under-14 boys and girls.

Competitors hail from throughout Australia.

TIGS student Tahlia, 14, and Kiama High student Cooper, 12, have been putting in the extra training hours ahead of the prestigious event, working with their coaches Nick Clifford and Brett Connellan.

Tahlia will compete in the under-16 girls, while Cooper will take part in the under-14 boys’ division.

Both have competed in regional and state events in the past, as well as events such as Barton Lynch's BL’s Blast Off.

They're also members of the Jones Beach Boardriders, while Tahlia was recently selected for the Illawarra Academy of Sport's surfing program.

“They'll be so many good people from around the country, and I reckon it'll be a really tough one, but I reckon it'll be really exciting too,” Tahlia said of the Manly event.

“I've been trying to surf my best every day,” Cooper said.

“They'll be tonnes of good surfers from around Australia there… But you can learn so much from them and just do your best.”

Both siblings have enjoyed a life-long love of the water.

“I've just always liked the feeling of being able to just be going across a wave; it's just so freeing and you can forget all your worries,” Tahlia said.

“I love the feeling of just getting in the water, getting refreshed and washing out all your worries and everything, and then you have a nice, fun surf,” her brother said.

The festival will feature some of the world’s best athletes, including 2016 women’s world surfing champion Tyler Wright and surfing superstar Julian Wilson.

Joining them will be six of the world’s top ten-ranked World Surf League female surfers including Gerroa product Sally Fitzgibbons.

Both surfing and skateboarding are set to debut at the 2020 Olympics in Tokyo.